为了进一步研究高速公路路径识别中标识站选址问题，以路网拓扑结构为基础，采用生成 树理论对标识站的优化选址进行了分析。首先，给出了标识站选址原则，并根据图论的相关理论 基础，提出了标识站的选址定理，确定了标识站的最优数量。然后，建立了标识站选址的优化模 型，根据数量最少和OD反推原则确定了标识站选址的约束条件，通过流量较小的原则建立标识 站最优选址的目标函数。同时，提出了基于关联矩阵实现大型路网标识站最优选址的算法。最 后，通过算例阐述了利用模型解决高速公路标识站选址问题的求解过程。计算结果表明，该模型 能够实现标识站的最优选址，符合高速公路联网收费中通行费精确拆分的实际需求。

In order to further study the location of identification station in expressway routes identifica⁃ tion, based on road network topology, the optimal location of identification station were analyzed by us⁃ ing spanning tree. Firstly, the principles were summarized, and location theorem was put forward accord⁃ ing to the relevant theoretical basis of graph theory, and the optimal numbers of identification station were given. Then, optimal locating model of identification station was established, the restrictions of identification station location were determined based on the principle of minimum number and O-D esti⁃ mation, and objective function was established based on the principle of road section with small flow. And based on associated matrix, the algorithm which was suitable for optimal location of identification station in large-scale road network was proposed. Finally, the solving processes applying the optimal lo⁃ cating model to solve the location of expressway identification station were expounded with a numerical example. The results show that the model achieves good effect on the optimal location of identification station, which meets the actual needs of precise toll allocation in networking toll.